/******************************************************************************
 * Copyright (c) 2006, 2010 VMware Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Apache License v2.0 which accompanies this distribution. 
 * The Eclipse Public License is available at 
 * http://www.eclipse.org/legal/epl-v10.html and the Apache License v2.0
 * is available at http://www.opensource.org/licenses/apache2.0.php.
 * You may elect to redistribute this code under either of these licenses. 
 *
 * Contributors:
 *   VMware Inc.
 *****************************************************************************/

package org.eclipse.gemini.blueprint.test;

import java.io.InputStream;
import java.util.Properties;

import org.eclipse.gemini.blueprint.test.internal.util.IOUtils;
import org.eclipse.gemini.blueprint.test.internal.util.jar.JarCreator;
import org.osgi.framework.BundleContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.util.StringUtils;

/**
 * Abstract JUnit base class that allows easy OSGi integration testing. It
 * builds on its super classes to allow full configuration of the underlying
 * OSGi platform implementation, of the test bundle creation (including the
 * manifest automatic generation).
 * <p/>
 * <p/>This class follows the <em>traditional</em> Spring style of integration
 * testing in which the test simply indicates the dependencies, leaving the rest
 * of the work to be done by its super classes. Consider the following simple
 * example:
 * <p/>
 * <pre class="code">
 * public class SimpleOsgiTest extends AbstractConfigurableBundleCreatorTests {
 * <p/>
 * public void testOsgiPlatformStarts() throws Exception {
 * System.out.println(bundleContext.getProperty(Constants.FRAMEWORK_VENDOR));
 * System.out.println(bundleContext.getProperty(Constants.FRAMEWORK_VERSION));
 * System.out.println(bundleContext.getProperty(Constants.FRAMEWORK_EXECUTIONENVIRONMENT));
 * }
 * }
 * </pre>
 * <p/>
 * <p/> The above class can be ran just like any other JUnit test. Equinox
 * platform will be automatically started, the test will packed in an OSGi
 * bundle (with its manifest created automatically) which will be deployed
 * inside the OSGi platform. After running the test inside the OSGi environment,
 * the test results (whether they are exceptions or failures) will be reported
 * back to the running tool transparently. Please see the reference
 * documentation for more examples, customization tips and help on how to do
 * efficient and fast integration testing.
 * <p/>
 * <p/> This class allows the test on-the-fly bundle (jar) can be configured
 * declaratively‎ by indicating the locations for:
 * <ul>
 * <li>root folder ({@value #ROOT_DIR}) - the starting point on which the
 * resource patterns are applied</li>
 * <li>inclusion patterns ({@value #INCLUDE_PATTERNS})- comma separated
 * strings which identify the resources that should be included into the
 * archive.</li>
 * <li>manifest ({@value #MANIFEST})- the location of the manifest used for
 * testing (if automatic generation is undesired).</li>
 * </ul>
 * <p/> These settings can be configured by:
 * <ul>
 * <li>using a properties file. By default the property name follows the
 * pattern "[testName]-bundle.properties", (i.e. /foo/bar/SomeTest will try to
 * load file /foo/bar/SomeTest-bundle.properties). If no properties file is
 * found, a set of defaults will be used.</li>
 * <p/>
 * <li>overriding the default getXXX methods and providing an alternative
 * implementation.</li>
 * </ul>
 * <p/>
 * <p/>Another useful functionality inherited from
 * {@link AbstractOnTheFlyBundleCreatorTests} class is the ability to create a
 * manifest for the test bundle on the fly, based on the classes present in the
 * archive.
 * <p/>
 * <p/><b>Note:</b> This class is the main testing framework entry point
 *
 * @author Costin Leau
 * @see AbstractOnTheFlyBundleCreatorTests
 */
public abstract class AbstractConfigurableBundleCreatorTests extends AbstractOnTheFlyBundleCreatorTests {

    protected static final String ROOT_DIR = "root.dir";

    protected static final String INCLUDE_PATTERNS = "include.patterns";

    protected static final String LIBS = "libs";

    protected static final String MANIFEST = "manifest";

    private static final Properties DEFAULT_SETTINGS = new Properties();

    static {
        DEFAULT_SETTINGS.setProperty(ROOT_DIR, Thread.currentThread().getContextClassLoader().getResource(".").toString());
        DEFAULT_SETTINGS.setProperty(INCLUDE_PATTERNS, JarCreator.EVERYTHING_PATTERN);
        DEFAULT_SETTINGS.setProperty(LIBS, "");
        DEFAULT_SETTINGS.setProperty(MANIFEST, "");
    }

    /**
     * Settings for the jar creation. Static as it has to be cached between test
     * runs and it is being initialized once in
     * {@link #postProcessBundleContext(BundleContext)}.
     */
    private static Properties jarSettings;


    protected String getRootPath() {
        return jarSettings.getProperty(ROOT_DIR);
    }

    /**
     * {@inheritDoc}
     * <p/>
     * <p/>Ant-style patterns for identifying the resources added to the jar.The
     * patterns are considered from the root path when performing the search.
     * <p/>
     * <p/> By default, the content pattern is <code>*&#42;/*</code> which
     * includes all sources from the root. One can configure the pattern to
     * include specific files by using different patterns. For example, to
     * include just the classes, XML and properties files one can use the
     * following patterns:
     * <ol>
     * <li><code>*&#42;/*.class</code> for classes
     * <li><code>*&#42;/*.xml</code> for XML files
     * <li><code>*&#42;/*.properties</code> for properties files
     * </ol>
     *
     * @return array of Ant-style pattern
     */
    protected String[] getBundleContentPattern() {
        return StringUtils.commaDelimitedListToStringArray(jarSettings.getProperty(INCLUDE_PATTERNS));
    }

    protected String getManifestLocation() {
        return jarSettings.getProperty(MANIFEST);
    }

    /**
     * Returns the settings location (by default, the test name; i.e.
     * <code>foo.bar.SomeTest</code> will try to load
     * <code>foo/bar/SomeTest-bundle.properties</code>).
     *
     * @return settings location for this test
     */
    protected String getSettingsLocation() {
        return getClass().getName().replace('.', '/') + "-bundle.properties";
    }

    /**
     * Returns the default settings used when creating the jar, in case no
     * customisations have been applied. Unless the base class is used as a
     * testing framework, consider using a properties file for specifying
     * specific properties for a test case.
     *
     * @return default settings for creating the jar
     * @see #getSettingsLocation()
     */
    protected Properties getDefaultSettings() {
        return DEFAULT_SETTINGS;
    }

    /**
     * Returns the settings used for creating this jar. This method tries to
     * locate and load the settings from the location indicated by
     * {@link #getSettingsLocation()}. If no file is found, the default
     * settings will be used.
     * <p/>
     * <p/> A non-null properties object will always be returned.
     *
     * @return settings for creating the on the fly jar
     * @throws Exception if loading the settings file fails
     */
    protected Properties getSettings() throws Exception {
        Properties settings = new Properties(getDefaultSettings());
        // settings.setProperty(ROOT_DIR, getRootPath());
        Resource resource = new ClassPathResource(getSettingsLocation());

        if (resource.exists()) {
            InputStream stream = resource.getInputStream();
            try {
                if (stream != null) {
                    settings.load(stream);
                    logger.debug("Loaded jar settings from " + getSettingsLocation());
                }
            } finally {
                IOUtils.closeStream(stream);
            }
        } else {
            logger.info(getSettingsLocation() + " was not found; using defaults");
        }

        return settings;
    }

    /*
     * Loads the jar settings, first from the disk falling back to the default
     * settings, if none is found.
     */
    protected void postProcessBundleContext(BundleContext context) throws Exception {
        // hook in properties loading

        // reset the settings (useful when running multiple tests)
        jarSettings = null;
        // load settings
        jarSettings = getSettings();
        // Somehow the JarCreator needs to get this
        jarCreator.setRootPath(getRootPath());

        super.postProcessBundleContext(context);
    }

}
